/Engine/Source/Runtime/SignalProcessing/Public/DSP/Dsp.h
Calculates equal power stereo pan using sinusoidal-panning law and cheap approximation for sin InLinear pan is [-1.0, 1.0] so it can be modulated by a bipolar LFO
namespace Audio { static void Audio::GetStereoPan ( const float InLinearPan, float & OutLeft, float & OutRight ) }